While many organizations may be attracted by the potential benefits of an executive information system (EIS), the development and implementation costs can be very difficult to estimate. Such uncertainty leads naturally to consideration of prototyping. It is the argument of this paper that the best area in which to prototype is the IS functional area and that an EIS for the Chief Information Officer (CIO) represents the full range of challenges in implementation. A case study of such a system in a global organization is reported in which the regional CIO for a global organization was able to solve two problems in a single move. The first problem was the need to evaluate the potential within the organization for EISs. The second was his increasing difficulty in keeping informed and in contact with all developments within his area of responsibility, which included data centre operations and project development in a dozen countries. The solution was a prototype EIS to meet his own needs. As a prototype it was satisfactory in that the CIO's area of responsibility covered all of the functions normally included in an EIS. In terms of meeting information needs, the EIS was shown to be most valuable to the CIO.